My boyfriend & I have an 11 mo. old male chow & I want to start by saying that words truly cannot explain how much we love him. We put him before ourselves & take him everywhere with us for companionship & socialization. He frequents countless stores, malls, outdoor restaurants & festivals with us. Strangers' children as small as his height give him bear hugs when they see him & he reciprocates with kisses. We have a dog bicycle cart with a battery operated fan in it so that he can accompany us on bike rides as we know his endurance would not allow for him to jog alongside. From the time he was fully vaccinated we took him to doggie daycare 5 days a week while we were at work & he had acres of fenced yard to play with other dogs. Since he's gotten a little older we have cut down on the number of days we take him to daycare to about once a week. He started developing some bad behaviors we attributed to those visits. They were things such as jumping up on people (which we've seen the workers sometimes encourage to say hi) and he started seeming to "challenge" us by pouncing from side to side and barking at us out of nowhere. We assumed he might be doing this with another dog at daycare when playing, even though we have never seen him do anything but run alongside other dogs at the park & at home. Most of our neighbors have dogs that range from little yorkies to various large breeds & he loves them all & plays very respectfully.

I prefaced with all of that so that you understand it came as a GREAT surprise when just last week he suddenly broke out into a severe burst of energy in the house, but instead of zooming around, he went up to my boyfriend, pounced back & forth & barked at him & then proceeded to start biting at him. Several bites made contact in passing but one was very intentional & left him bruised & in pain. The entire time my boyfriend loudly & sternly told him "no" & nothing fazed him. We had to work together to get ahold of his harness & lead him into his "room" (we have a 15-20 sq. ft. tiled area with mounted baby gates that serves as his pen when he needed to be enclosed as a puppy when we were not home). It was honestly frightening & we were baffled as to what would have caused it. He's seemed a little on edge lately as well. For instance, when we brush him each night we call him over, tell him to sit, and then gently lead him to lie down on his side for the brushing. Lately, he decides when he is in the mood for it because when he is not, he will quickly throw his head back & jump out of my arms when I attempt to lie him down. Nervous because of what happened last week, I do not push the matter & leave him be. I attributed it to him possibly being hot even though we keep the cold for him (a bit too cold for our liking) & I attempted to brush him while he was on the cool tile.

Just this evening, we went outside with him once the sun had mostly set so it had cooled off. We were standing in the yard when, again out of nowhere, he suddenly had the exact same biting fit with my boyfriend. He broke skin this time & caused my boyfriend to sit down in pain. He proceeded to go up behind him & attempt to bite at his back, but we had him on a long tie out & I quickly grabbed hold of it to pull him back from my boyfriend. I tried to grab his harness & he turned on me as well. He was unable to break skin & we had to both grab hold of him & hold him down while I got his leash attached to him. He snapped out of it once his leash was on and I cautiously led him inside & into his room.

I type all of this with such a heavy heart, because he means the world to us & we are very worried that this will continue. We never have to gate him in & it is breaking our hearts to see him in there right now, not lying by us on the tile.

We cannot find any common denominators between the two incidents so we know that we need outside advice/help on this matter. He has not been neutered yet as we wanted to give him lots of time for his growing body & bones to fully develop. We aren't sure if this could be a reason for the sudden outbursts but we are grasping at straws to think of any reason he would have to do what he did.

We are looking for any advice our fellow chow owners might have. Furthermore, we welcome & would appreciate any chow-experienced trainer recommendations. We love him dearly & are willing to travel or make any feasible arrangements if we find a capable trainer with proven results regarding behavior like our chow's.

Any & all advice/help is very much appreciated as this matters is obviously extremely close to our hearts. We want to resolve it & train him with a reliable command should any future incidents happen. Thank you in advance for your time & advice.

Without getting too much into it, the common denominator is the outside area. The energy burst you describe sounds like play and not aggression. Again, not being there I can't say for sure, but I have a dog that exhibits similar behavior. He wants to bob and weave and jump up when outside on the trolley run. He will do this everytime my wife comes home from work and parks the car in the drive. He is on a lead, so I can step on it to prevent him from jumping up. When he displays this toward me, I will play with him for a bit, instructing him to 'put the teeth away'. When he does, I will pet him. If not I keep my hands and arms tucked and ignore him. He calms quickly and realizes that his play is inappropriate. Now we have 2 males and a female. He hates being played at with the other dogs, always has. But he is respectful of them and just gives them a quick warning, we have never had any actual arguments or fights. My 7 month old male chow is getting to the challenge age, and I have to push them back from each other before anything escalates, but its a similar situation.

Again, this doesn't sound like aggressive behavior, but its still not appropriate. He needs to learn that leading with his teeth can't happen. I would wonder whether nipping was allowed as a pup.

BTW, great job on socializing him. That will go a great distance in correcting his behavior. I would recommend a couple sessions outside in his zone with either a favorite toy or a treat. Gather his attention with those items and redirect his focus.

It sounds like you are doing a wonderful job with your boy. I think Rory gave your some great ideas. I would strongly suggest that you take to your vet and have a complete exam also. This should include complete bloodwork and a thyroid test. There may be a medical reason for the change in his behavior.